/Engine/Source/Developer/WidgetRegistration/Public/ToolkitBuilder.h
Returns a TSharedPointer to the FToolbarBuilder with the FUICommandInfos that load the Palettes
[TSharedPtr](API\Runtime\Core\Templates\TSharedPtr)< [FToolBarBuilder](API\Runtime\Slate\Framework\MultiBox\FToolBarBuilder) > GetLoadPaletteToolbar()